The magnitude of alcohol related problems in the United States is staggering, with 20-40% of all hospital beds being occupied by patients with alcohol-induced and/or related problems. The fiscal costs are estimated at greater than $100 billion annually. Currently, carbohydrate- deficient transferrin (CDT) is the best available marker for the diagnosis of alcohol abuse and for monitoring abstinence. The specific aims of this proposal are to discern the biochemical composition of CDT isoforms present in the sera of alcohol abusers by analyzing purified transferrin samples to determine the carbohydrate content, the nature of the protein/carbohydrate linkages, distribution of glycans, monosaccharide compositional analysis and oligosaccharide sequence. This information will be utilized to develop a quantitative fluorescent incorporation assay (FIA) whereby fluorescent sialic acid analogues are enzymatically introduced into carbohydrate- deficient glycoproteins in the sera of alcohol abusers. The long-term objectives are to adapt the quantitative FIA to a microtiter plate format and to make the assay commercially available. PROPOSED COMMERCIAL APPLICATION: Nearly 15 million adults in the United States are alcohol-dependent. A low-cost, second generation procedure, based on the incorporation of fluorescent analogues into carbohydrate- deficient serum glycoproteins, will be developed for the diagnosis of alcohol abuse. Additional potential applications include screening of neonates for a newly described group of systemic inherited neurological diseases, i.e., the